The Doctrine Project is the home to several PHP libraries primarily focused on database storage and object mapping. The core projects are a Object Relational Mapper (ORM) and the Database Abstraction Layer (DBAL) it is built upon.

Omeka is a free, flexible, and open source web-publishing platform for the display of library, museum, archives, and scholarly collections and exhibitions. Its “five-minute setup” makes launching an online exhibition as easy as launching a blog.

Waterbear is a toolkit for creating drag-and-drop programming languages, with some example languages you can play around with and learn from. The goal is to make it easy to wrap other existing languages with Waterbear blocks to create draggable, snappable syntaxes for them.